In a typical internal drum type laser imagesetter, a section of a web of recording media is drawn from a supply roll and subsequently positioned on the surface of a drum shaped media support surface. During an initial loading procedure, the leading end of the recording media is pulled off the supply roll and directed onto the surface of the internal drum, ultimately passing out of the internal drum through an exit aperture. Thereafter, an image scanning system directs a focused, modulated, exposure beam (e.g. scanning laser beam) across the recording media, producing a series of exposed scan lines representing an image to be recorded.
Under optimal conditions, where surface to surface contact is maintained as the recording media is directed over the surface of the internal drum during the initial loading procedure, the leading end of the recording media will usually pass out of the internal drum through the exit aperture without jamming. In practice, however, the leading end of web-fed recording media will commonly lift or curl away from the surface of the internal drum, oftentimes jamming within the drum before successfully passing through the exit aperture. The problem of media curl is even more prevalent when the section of the recording media to be loaded onto the surface of the internal drum is drawn off the end of the supply roll, where the relative curvature of the recording media is the greatest.
Accordingly, it is a specific object of the present invention to significantly reduce media jamming during an initial media loading procedure by maintaining and maximizing surface to surface contact between the recording media and the surface of the internal drum as the leading end of the recording media is passed over the drum surface toward and/or into the exit aperture of the drum.
It is a further object of the present invention to significantly reduce media jamming, lifting and buckling during subsequent media feeding procedures by maintaining surface to surface contact between the recording media and the surface of the internal drum.